en_tn/num/01/20.md

the names of all the men twenty years old or older, able to go to war, were counted

This can be stated in active form. Alternate translation: "they counted by name all the men twenty years old or older, able to go to war" (See: rc://en/ta/man/jit/figs-activepassive)

older, able to go to war, were

"older—men who were able to go to war—were"

counted man by man

"counted one by one" or "counted head by head"